As electronic devices have become smaller in size and higher in performance in recent years, more and more electronic parts are fabricated on chips. As such, there is a growing demand for packaging such on-chip electronic parts on a mass-production basis, for example, on an elongated tape using an automatic inserting machine.
A chip mounter, also known as a “chip shooter” or “placement machine,” is one apparatus used for high-speed, high-precision mounting of electronic chips fed from a feeder to preset positions of a printed circuit board. In some instances, the chip mounter includes suction nozzles of a head are used to mount electronic chips. With the recent trend toward multifunctional, high-specification and downsized electronic devices, the need is increasing to develop techniques for high-density mounting of electronic chips on printed circuit boards of the electronic devices.
Recently, technology for mounting chips on printed circuit boards is shifting from through-hole mounting to surface mounted technology (SMT). Surface mounted technology is used to directly mount chips in high density on the surface of printed circuit boards. Surface mounting devices (SMDs) for use in surface mounted technology may include tape roll or tray and stick types, depending on the feeding form of chips. Chip mounters may also be classified into tape feeders, tray feeders, and stick feeders by their chip feeding mode and/or according to the type of surface mounting devices. Of these, the most widely used are tape feeders that feed chips in the form of carrier tapes. An advantage of tape feeders is the ability to feed a large number of chips at high speeds.
A typical carrier tape consists of a base tape, storage spaces formed at regular pitches in the base tape, and a cover tape attached to an upper surface of the base tape. Small-sized electronic components, such as semiconductor chips, may be accommodated in the storage spaces of the base tape. The cover tape is then secured on the upper surface of the base tape to protect the electronic chips. Due to this construction, the carrier tape functions as a vehicle for feeding the electronic chips, into the chip mounter.
In one prior art approach, carrier tape may include a base tape made of paper and having transport holes formed at regular intervals at one lateral side thereof. The base tape may have storage spaces with a predetermined depth to accommodate devices therein. The cover tape may be made of a transparent polymer film adhesively attached to the base tape. While a tape feeder locks the transport holes of the base tape to move the carrier tape by specific pitches, the cover tape is separated from the base tape and the storage spaces are exposed so that the electronic chips can be picked-up by suction nozzles of a mounter. However, once the electronic chips are removed, the base tapes and cover tapes are separately discharged, thus requiring additional equipment and cost to accommodate the by-product.